Dispensing pump



Sept. l1, 1934. w. F. ESSEX DISPENSING PUMP Filed oct. 51, 1932 ATTORNEY Patented Sept. 11, 1.934 i lUNITED STATES PATENT OFFICE DISPENSING PUlHP William F. Essex, Chicago, Ill., assignor to Standard Oil Company, Chicago, lll., a corporation of Indiana I Application October 31, 1932, Serial No. 640,428

` 11 Claims. (o1. 221-95) This invention relates to improvements for disthereby breaking the electrical contact leading to pensing pumps and particularly to improvements the motor 17. When the nozzle check valve is for dispensing pumps adapted to handle gasoline removed from the hook 26, the spring 29 forces and similar volatile liquids. the rod 2'7 and hook 28 upwardly and thereby In the process of dispensing gasoline and simicloses the electrical circuit leading to the motor 60 lar volatile liquids with the conventional type and starts the rotor pump. It is clear that the of dispensing pump, for example, the type of dismotor and pump continue to run as long as the pensing pump which comprises a pump and disnozzle check valve is off the hook 26. pensing conduit, considerable trouble results from When the dispensing pump isused, the'nozzle the thermal expansion of the volatile fuels with- 25 is removed from the hook -26 which in turn 65 in the closed system. starts the motor 17 and pump 16. The nozzle An object of my invention is to provide a check valve 25 is then opened by pressing the chamber that will compensate for the thermal exhandle 30 and gasoline is then pumped from the pansion of the gasoline or similar volatile liquids storage talk 13 through the strainer 14, pump 15 within the dispensing pump. 16, meter 20, visible flow gage 23 and through the 70 Another object of my invention is to provide an conduit 24 to the nozzle check valve 25. After the expansion chamber that will not become filled desired amount of gasoline has registered on the with gasoline upon continued use. recording device 21 the nozzle check Valve 25 is A further object is to provide an expansion quickly closed by releasing the handle 30. After chamber that will compensate for the loss of gasthe nozzle check valve 25 has been closed, the 75 Cline in the line leading t0 the Pump. motor .'17 and pump 16 continue to run until the My invention will be more fully understood nozzle is hung on the hook 26. A bypass valve from the following description when read in con- 31 is provided on the pump 16 to prevent an exnection with the drawing, in which: cess pressure from building up in the lines lead- 25 Figure 1 represents an elevational view of the ing from the pump to the nozzle check valve when sc dispensing DllInP- said nozzle is olf the hook. The bypass 31 is ad- Figure 2 represents a. vertical section through justed to open when the pressure in the line 19 one type of expansion chambers suitable for my builds up to about 12 or 15 pounds. However, invention. Ahis may vary withv different types of pumps.

The Operating mechanism 0f the dispensing. During the hot seasons the gasoline that is g5 pump is mounted on a suitable framework 10, trapped between the check valve 32 on the underwhich Ais supported by a base plate 11. A conground tank 13 and the nozzle check valve duit 12, which leads to the underground tank 13, 25, expands and creates considerable pressure passes up through the base plate to the strainer throughout the closed pipe system of the pump 35 14 where any foreign material is removed from if a means is not provided to compensate for this 90 the gasoline or uid that is being dispensed. A thermal expansion. When the dispensing pump conduit 15 connects the exit of the strainer 14 is idle for a relatively short period of time, the with a suitable propelling means such as a rotor thermal expansion of the gasoline creates prespump 16 which is driven by the motor 17 through sures as high as '15 to 30o pounds per square inch the belt or chain 18. A conduit 19 connects the within the closed system of the dispensing pump, 95 Onile` 01' DreSSlne Side 0f Said pump to a meter and as a result leaks form throughout the closed ing device 20. A recording device 21 is actuated pipe system and sometimes the flexible hose 24 by said meter andthe amount of gasoline or bursts. Heretofore the prior art has sought to fluid that ows through the meter is recorded compensate for this thermal expansion of the i5` on said device. A conduit 22 connects the exit gasoline by placing a compression chamber filled 100 of said meter with a visible flow gage 23, and a with air on the exit side of the pump 16, but such flexible hose 24 connects the Visible 110W gage chambers have proven to be inoperative. When with a normally Closed Home Valve 25- the chamber is so placed on the exit side of the A hOOk 26 iS DIOVded at a CODVenient Place 0n pump it ills up with gasoline and ceases to functhe pump for holding the nozzle check valve 25 tion as a means to compensate for the thermal 105 when said nozzle check valve is not being used. expansion. The explanation of the inoperative- The hook 26 `is adapted to move downwardly when ness of the chamber is believed to be as follows: the nozzle 25 is hung thereon. The downward Gasoline is forced into the chamber under presmovement of the hook causes the rod 27 to move sure because it is on the pressure side of the pump,

downwardly and open the electrical switch 28, and after a short period of time the au' contained 110 within the chamber. is dissolved in the gasoline and the liquid gasoline takes the place of the air.

At all times the gasoline in the compression cham-` ber is under some pressure and it is never withdrawn. Even when the nozzle check valve 25 is opened, the pressure in the line leading from the pump to the nozzle is not sufliciently reduced to withdraw the gasoline from the compression chamber.

According to this invention, I have found that an expansion chamber 33 connected to the inlet or suction side of the pump and also to the outlet or pressure side of the pump will compensate for the thermal expansion of the gasoline trapped between check valve 32 and nozzle check valve 25. The expansion chamber 33 is connected by a small conduit 34 to the suction side of the pump 16, as shown at 16a, and another conduit 35 is connected to the conduit 19 on the pressure side of the pump 16, as shown at 35a. It should be understood that the line 34 may be connected at any point between the check valve 32 and the intake of the rotor pump 16, but preferably at a point near the inlet side of the pump. The conduit 35 may be connected at any point in the line between the outlet side of the pump 16 and the see-gage 23.

The expansion chamber 33 should be constructed to withstand considerable pressure and the chamber may be made of any design and should be of at least one liter capacity, although compression chambers of 1/2 liter capacity have been successfully used. A lug 36, or any other suitable means, is fastened to the chamber and is provided with holes to receive a U-shaped clamp 37 which detachably secures the chamber to the framework 10. The expansion chamber may be positioned at any point along the frame member 10, for example it may be placed below the level of the pump 16 or it may be placed at the level of the see-gage 23, or any intermediate point. The conduits 34 and 35, which connect the expansion chamber to the inlet and outlet side of the pump, may be of any suitable size, but preferably from 1/8 to 1/2 inch in diameter. Instead of having the compression chamber made separate from the other mechanisms of the pump, the chamber may be made integral with the lter 14 or pump 16,v

but in either case the compression chamber must be connected to both the inlet and outlet sides of the pump.

Figure 2 shows a cross sectional view of one embodiment of the expansion chamber. The lower part of the expansion chamber is provided with a bushing 38 threadedly secured to the compression chamber, and a pipe coupling 39 is attached to the lower part of the bushing for connecting the line 34 to the expansion chamber. The face of the bushing projects -into the chamber and is provided with a ball-valve seat 40, the iloat valve adapted to control the flow of liquid from the expansion chamber comprises a ball 41 with a cork oat 42 attached thereto by the rod 43 and nut 43a. The float may be coated with a suitable n gasoline insoluble composition, or it may be made of metal. A hook 44, or other suitable stopping means, is attached to the lower part of the ballvalve by the arm 45 and disposed in the enlarged portion of the bushing, thereby permitting the ball-valve 41 to be raised only a short distance from its seat.

One side ofthe expansion chamber is provided with an internally threaded boss 46 which is adapted to receive the coupling 47 for the line 35 that leads to the pressure or exhaust side of the pump 16. The opening through the boss leads to the interior of the chamber and terminates in a cap 48 which is provided with small outlets as shown at 49. Secured to the top of the cap is a bell-shaped hood 50, which extends around and in a spaced relation with the periphery of the cap and terminates beyond the openings in said cap. i

By the use of the expansion chamber attached to both the inlet and outlet sides of the dispensing pump, the thermal expansion of the gasoline in the closed pipe system of the dispensing pump is compensatedfor to such an extent that it is very difficult to detect the slightest increase in pressure during the hot seasons. When the pump 16 is started, the gasoline is forced through the line 19 and to or through the nozzle 25, and a small proportion of gasoline is also forced into the chamber 33 through the line 35 until the pressure of the air or vapors therein exceed the pressuresetting on the by-pass valve 31. Usually the by-pass valve is set for about 10 -to 15 pounds pressure per square inch. As the gasoline begins to collect in the expansion chamber 33, the float 42 raisesV the ball check valve 41 from its seat and permits some of the gasoline to ilow out of the chamber and into the suction side of the pump. By this operation, a small amount of `gasoline is circulated through the expansion chamber and as a result of this circulation a supply of air is always present in the expansion chamber. When the pump 16 is stopped, the valve 41 remains off its seat until the gasoline in the expansion chamber will no longer support theoat 42. As long as the ball valve remains open, the expansion chamber also serves as a reservoir and will compensate for thegasoline that leaks back into supply tank 13 through theI check valve 32. However, the float valve seats before all of the liquid ilows from the expansion chamber, thereby maintaining a portion of liquid in the expansion chamber at all times.

If desired, I may use an expansion chamber that does not have a valved opening. In such cases, the ow pipe leading from the intake conduit communicates with the bottom of the expansion chamber, and the small pipe leading from the outlet side of the pump communicates with the side or top of the expansion chamber. This type of construction is not as satisfactory as the construction where the small conduit from the suction line is provided with a valved opening in the expansion chamber, because this modification does not assure the maintenance of a small amount of liquid in the expansion chamber.

As a, further modification of my invention, the boss 46 may be placed in the bottom of the expansion chamber adjacent the float valve 41, instead of being disposed on one side of the expansion chamber. Also instead of using the float valve 41 and 42 as herein described, I may use any 135 other suitable valve that opens when the pressure or level of gasoline within the expansion chamber exceeds a predetermined amount.

I have described my invention with reference to a wet hose type, of pump, that is, the type of 11:9 pump where the flow of liquid is controlled by a nozzle check valve on the end of the dispensing conduit, but it should be understood that I may use the compression chamber on 'the inlet and exit side of any type of pump or dispensing means.

While my invention has been described with reference to a gasoline dispensing pump, it should be understood that other similar liquids may be dispensed from the pump. The scope of my invention is to be determined lily-.the following claims and not by the specic disclosure as hereinabove set forth.

I claim: i

l. In a liquid dispensing apparatus a storage tank for liquid, pumping means for withdrawing liquid from the tank, a suction line connecting the pump and tank, a check valve in said line preventing return ow of the liquid drawn by said means, a delivery conduit, a normally closed valve controlling the outlet of said conduit, and an expansion chamber adapted to contain liquid and air under pressure connected to the suction side and the exhaust side of said pumping means.

2. In liquid dispensing apparatus, a storage tank for liquid, a pumping means for withdrawing liquid from the tank, a suction pipe connecting the pump and tank, a check valve on said pipe preventing return flow of the liquid drawn by said means, a delivery conduit, a normally closed valve controlling the outlet of said conduit, an expansion chamber adapted to contain liquid and air under pressure, a conduit of relatively small cross sectional area as compared to said pipe and conduit for connecting said chamber to the suction side of the pumping means, and a conduit of relatively small cross sectional area as compared to said pipe and conduitl for connecting said chamber to the outlet side of the pumping means.

3. In a liquid dispensing apparatus, a storage tank for liquid, a pumping means for withdrawing liquid from-the tank, a suction pipe connecting the tank and pumping means, a delivery conduit leading from the outlet side of the pumping means, an expansion chamber adapted to contain liquid and air under pressure provided with a valved passageway disposed in the bottom thereof for controlling the flow of liquid through said passageway, a small conduit communicating with the suction pipe and the valved passageway on the expansion chamber, and a small conduit communicating with the delivery conduit and the expansion chamber.

4. In a liquid' dispensing apparatus, a storage tank for liquid, a pumping means for withdrawing liquid from the tank, a suction line connecting the pump and tank, a delivery conduit, an expansion chamber having two openings, one of said openings provided with a valve for controlling the now of liquid from the expansion chamber adapted to contain liquid and air under pressure when the quantity of liquid 'therein has reached a predetermined amount, a small conduit connecting the suction line with the valved opening in the expansion chamber, another small conduit for connecting the delivery conduit with the other opening in the expansion chamber.

5. In a liquid dispensing apparatus, a storage tank for liquid, a pumping means for withdrawing liquid from the tank, a suction line connecting the pump and tank, a delivery conduit, an expansion chamber adapted to contain liquid and air under pressure having two openings, one of said openings provided with a float valve for controlling the flow of liquid from the expansion chamber when the quantity of liquid therein has reached a predetermined amount, a small conduit connecting the suction line with the valved opening in the expansion chamber, another small conduit for connecting the delivery conduit with the other opening in the expansion chamber.

6. In a liquid dispensing apparatus, a storage tank for liquid, a pumping means for withdrawing liquid from the tank, a suction line connecting the pump and ,tank,. a delivery conduit, a. normally closed valve controlling'the outlet of said delivery conduit, expansion chamber adapted to contain liquidand air under pressure having'two openings, one ,of saidl openings provided with a valve for ,controlling-the flow .ofzliquid from the expansion chamber when the quantity of liquid therein has reached a predetermined amount, a small conduit connecting the suction line with the valved opening in the expansion chamber, an-

other small conduit connecting the delivery conduit with the other opening in the expansion chamber.

7. In a liquid dispensing apparatus, a storage tank for liquid, a pumping means for withdrawing liquid from the tank, a suction line connecting the pump and tank, a check valve in said pipe for preventing return ow of the liquid drawn by said means, a delivery conduit, a normally closed Valve controlling the outlet of said delivery conduit, an expansion chamber adapted to contain liquid and air under pressure having two openings, one of said openings provided with a valve for controlling the ow of liquid from the expansion chamber when the quantity of liquid therein has reached a predetermined amount, a small conduit connecting the suction line with the valved opening in the expansibn chamber, another small conduit connecting the delivery conduit with the other opening in the expansion chamber.

8. In a liquid dispensing apparatus, a storage tank for liquid, a pumping means for withdrawing liquid from the tank, a suction line connecting the pump and tank, a check valve in said line for preventing return flow of the liquid drawn by said means, a delivery conduit, an expansion chamber having two openings, one of said openings provided with a valve for controlling the flow of liquid from the expansion chamber adapted to contain liquid and air under pressure when the quantity of liquid therein has reached a predetermined amount, a small -conduit connecting the suction line with the valve opening in the expansion chamber, another small conduit for connecting the delivery conduit with the other opening in the expansion chamber.

9. A dispensing pump comprising a propelling means, an inlet conduit communicating with said propelling means and a source of liquid, a check valve in said conduit for preventing return flow of the liquid drawn by said propelling means, 'an outlet conduit leading from said propelling means, an expansion chamber adapted to contain liquid and air under pressure provided with a valved passageway disposed in the bottom thereof for controlling the ow of liquid through said passageway, a small conduit connected to the inlet conduit and said valved passageway, and a small conduit `connecting the outlet conduit and the expansion chamber.

10. In a liquid dispensing apparatus, a storage tank for liquid, a pumping means for withdrawing liquid from the tank, a suction pipe connecting the tank and pumping means, a delivery conduit leading from the outlet side of the pumping means, and expansion chamber adapted to contain liquid and air under pressure provided with a valved passageway for controlling the flow of liquid through said passageway, a iiow conduit communicating with the suction pipe and the valved passageway on the expansion chamber, and a flow conduit communicating with the delivery conduit,A and the expansion chamber.

1l. In a liquid dispensing apparatus, a storage tank for liquid, pumping means for withdrawing duit, and an' expansin chamber adapted to con- #ein liquid and'air 'under pressure connected to the sucti'onside and the exhaust side of said pumping means whereby a small quantity of liquid can be' circulated through said expansion chamber.

" F. ESSEX. 

